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how to move horizontally using ImageButton in C# xamarin forms android?

I'm trying to move horizontally using ImageButtons in C# xamarin forms android.
My app looks like this:
What I want to do if it's possible is move horizontally using those ImageButtons. I'd like to touch the ImageButton and go through each StackLayout that my code generate dynamically. But I don't know how could I do that.
I will let my code here:
code page.xaml:
<AbsoluteLayout>
<ScrollView HorizontalScrollBarVisibility="Never" Orientation="Horizontal" HorizontalOptions="Center">
<StackLayout x:Name="imgs" Orientation="Horizontal" HorizontalOptions="Center">
</StackLayout>
</ScrollView>
<ImageButton x:Name="btnLeft" Clicked="btnMoveLeft" Source="drawable/left.png" WidthRequest="50" HeightRequest="50" AbsoluteLayout.LayoutBounds="0.009,0.5,100,100" AbsoluteLayout.LayoutFlags="PositionProportional"></ImageButton>
<ImageButton x:Name="btnRight" Clicked="btnMoveRight" Source="drawable/right.png" WidthRequest="50" HeightRequest="50" AbsoluteLayout.LayoutBounds="0.95,0.5,100,100" AbsoluteLayout.LayoutFlags="PositionProportional"></ImageButton>
</AbsoluteLayout>
code Page.xaml.cs:
private void btnMoveLeft(object sender, EventArgs e)
{
}
private void btnMoveRight(object sender, EventArgs e)
{
}
public void generateImg(MediaFile file2)
{
StackLayout stackLayout = new StackLayout();
stackLayout.Orientation = StackOrientation.Vertical;
StackLayout stackLayoutMinimo = new StackLayout();
Image im = new Image();
im.ClassId = contador.ToString();
im.Source = ImageSource.FromFile(file2.Path);
im.HeightRequest = 600;
im.WidthRequest = 400;
im.MinimumHeightRequest = 600;
im.MinimumWidthRequest = 400;
im.VerticalOptions = LayoutOptions.End;
im.HorizontalOptions = LayoutOptions.End;
im.Aspect = Aspect.AspectFill;
stackLayout.Children.Add(im);
Button deleteButton = new Button();
deleteButton.ClassId = contador.ToString();
deleteButton.Text = "Borrar imagen";
deleteButton.VerticalOptions = LayoutOptions.CenterAndExpand;
deleteButton.HorizontalOptions = LayoutOptions.Center;
deleteButton.MinimumWidthRequest = 100;
deleteButton.ClassId = contador.ToString();
deleteButton.AutomationId = contador.ToString();
deleteButton.Clicked += async (sender, args) => {
listDelete.Add(Convert.ToInt32(deleteButton.ClassId));
stackLayout.Children.Remove(im);
stackLayout.Children.Remove(deleteButton);
};
stackLayout.Children.Add(deleteButton);
imgs.Children.Add(stackLayout);
}
I hope someone can guide me. Thank you very much!

Just as Jason said, CarouselView is more suitable than ScrollView in your situation.
I made a demo by using CarouselView and you can refer to this.
Here is the code in Mainpage.Xaml:
<CarouselView ItemsSource="{Binding Photos}">
<CarouselView.ItemTemplate>
<DataTemplate>
<StackLayout>
<Frame HasShadow="True"
BorderColor="Gray"
CornerRadius="10"
Margin="25"
HeightRequest="350"
HorizontalOptions="Center"
VerticalOptions="CenterAndExpand">
<StackLayout>
<Label Text="{Binding Name}"
FontAttributes="Bold"
FontSize="Large"
HorizontalOptions="Center"
VerticalOptions="Center" />
<Image Source="{Binding Url}"></Image>
<Label Text="{Binding Location}"
HorizontalOptions="Center" />
<Label Text="{Binding Details}"
FontAttributes="Italic"
HorizontalOptions="Center"
MaxLines="5"
LineBreakMode="TailTruncation" />
<Button Text="Click"/>
</StackLayout>
</Frame>
</StackLayout>
</DataTemplate>
</CarouselView.ItemTemplate>
</CarouselView>
Here is the code in Mainpage.Xaml.cs:
public MainPage()
{
InitializeComponent();
this.BindingContext = new MyViewModel();
}
Here is the code in MyViewModel.cs and you can add data to it:
public class MyViewModel
{
public ObservableCollection<Photo> Photos { get; set; }
public MyViewModel()
{
Photos = new ObservableCollection<Photo>();
Photos.Add(new Photo() { Name = "Photos", Details= "Photos", Location= "Photos", Url= "Photos" });
Photos.Add(new Photo() { Name = "Photos", Details = "Photos", Location = "Photos", Url = "Photos" });
Photos.Add(new Photo() { Name = "Photos", Details = "Photos", Location = "Photos", Url = "Photos" });
}
}
Here is the code in Photo.cs:
public class Photo
{
public string Name { get; set; }
public string Location { get; set; }
public string Details { get; set; }
public string Url { get; set; }
}

SOLUTION
Finally, I use a CarouselView, it worked perfectly. With this code I resolved my problem. I left my code here. Maybe it helps someone.
code page.xaml:
<AbsoluteLayout>
<StackLayout Padding="5">
<CarouselView x:Name="carousel" HeightRequest="600" IndicatorView="{x:Reference contImgs}">
<CarouselView.ItemTemplate>
<DataTemplate>
<Image x:Name="activeImg" Source="{Binding Source}" Aspect="AspectFill"></Image>
</DataTemplate>
</CarouselView.ItemTemplate>
</CarouselView>
<IndicatorView x:Name="contImgs" IndicatorColor="#bbb" SelectedIndicatorColor="#000" IndicatorSize="12" IndicatorsShape="Circle"></IndicatorView>
</StackLayout>
<ImageButton Source="drawable/icon_trash.png" WidthRequest="100" Clicked="btnDeleteImg" HeightRequest="100" AbsoluteLayout.LayoutBounds="0.98,0.07,50,50" AbsoluteLayout.LayoutFlags="PositionProportional"></ImageButton>
<ImageButton x:Name="left" Clicked="btnMoveLeft" Source="drawable/left.png" WidthRequest="50" HeightRequest="50" AbsoluteLayout.LayoutBounds="0.009,0.5,100,100" AbsoluteLayout.LayoutFlags="PositionProportional"></ImageButton>
<ImageButton x:Name="right" Clicked="btnMoveRight" Source="drawable/right.png" WidthRequest="50" HeightRequest="50" AbsoluteLayout.LayoutBounds="0.95,0.5,100,100" AbsoluteLayout.LayoutFlags="PositionProportional"></ImageButton>
</AbsoluteLayout>
code Page.xaml.cs:
private List<Image> imgsCarrousel = new List<Image>();
public void generarImg (MediaFile file2)
{
StackLayout stackLayout = new StackLayout();
stackLayout.Orientation = StackOrientation.Vertical;
StackLayout stackLayoutMinimo = new StackLayout();
Image im = new Image();
im.ClassId = contador.ToString();
im.Source = ImageSource.FromFile(file2.Path);
im.HeightRequest = 600;
im.WidthRequest = 400;
im.MinimumHeightRequest = 600;
im.MinimumWidthRequest = 400;
im.VerticalOptions = LayoutOptions.End;
im.HorizontalOptions = LayoutOptions.End;
im.Aspect = Aspect.AspectFill;
stackLayout.Children.Add(im);
ImageButton deleteButton = new ImageButton();
deleteButton.ClassId = contador.ToString();
deleteButton.Source = "drawable/icon_trash.png";
deleteButton.HeightRequest = 50;
deleteButton.WidthRequest = 50;
deleteButton.VerticalOptions = LayoutOptions.CenterAndExpand;
deleteButton.HorizontalOptions = LayoutOptions.Center;
deleteButton.MinimumWidthRequest = 100;
deleteButton.ClassId = contador.ToString();
deleteButton.AutomationId = contador.ToString();
deleteButton.Clicked += async (sender, args) => {
listDelete.Add(Convert.ToInt32(deleteButton.ClassId));
stackLayout.Children.Remove(im);
stackLayout.Children.Remove(deleteButton);
};
stackLayout.Children.Add(deleteButton);
ImageButton imChica = new ImageButton();
imChica.ClassId = contador.ToString();
imChica.Source = ImageSource.FromFile(file2.Path);
imChica.HeightRequest = 100;
imChica.WidthRequest = 100;
imChica.MinimumHeightRequest = 100;
imChica.MinimumWidthRequest = 100;
imChica.VerticalOptions = LayoutOptions.End;
imChica.HorizontalOptions = LayoutOptions.End;
imChica.Aspect = Aspect.AspectFill;
imChica.Clicked += async (sender, args) => {
};
stackLayoutMinimo.Children.Add(imChica);
imgsMinimo.Children.Add(stackLayoutMinimo);
imgsCarrousel.Add(im);
}
Of course, finally i need this line to set the images in my Page.xaml.cs:
carousel.ItemsSource = imgsCarrousel;

SelectionChanged event of the CollectionView opens when the page is loaded

I have a CollectionView with the SelectionChanged event, which should be read as soon as certain items are selected or deselected. Actually the application enters into that event as soon as the page containing the CollectionView opens. How to solve?
xaml
<CollectionView
x:Name="CategoryView"
RelativeLayout.WidthConstraint="{ConstraintExpression
Type=RelativeToParent,
Property=Width,
Factor=1}"
RelativeLayout.YConstraint="{ConstraintExpression
Type=Constant,
Constant=60}"
Margin="10,0,10,0"
HeightRequest="700"
SelectionMode="Multiple"
SelectionChanged="CategoryView_SelectionChanged">
<CollectionView.Footer>
<Button
HeightRequest="120"
BackgroundColor="Transparent"/>
</CollectionView.Footer>
<CollectionView.ItemsLayout>
<GridItemsLayout Orientation="Vertical" Span="2" VerticalItemSpacing="1" HorizontalItemSpacing="4"/>
</CollectionView.ItemsLayout>
<CollectionView.ItemTemplate>
<DataTemplate>
<Grid BackgroundColor="{Binding myBackGroundColor}">
<Grid.RowDefinitions>
<RowDefinition Height="36"/>
<RowDefinition Height="33"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="30"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Image Grid.Row="0" Grid.RowSpan="2" Grid.Column="0" Grid.ColumnSpan="2" Source="{Binding Image}"/>
<Label Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2" Text="{Binding Titolo}" FontSize="19" FontAttributes="Bold" TextColor="White" Margin="13,0,0,0"/>
<Image Grid.Row="0" Grid.Column="0" Source="checked.png" IsVisible="{Binding Vis}" Margin="13,5,0,0"/>
</Grid>
</DataTemplate>
</CollectionView.ItemTemplate>
</CollectionView>
c#
private async void CategoryView_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
var selected = e.CurrentSelection;
ClassCategory model = e.CurrentSelection.FirstOrDefault() as ClassCategory;
WebClient clientw = new WebClient();
clientw.Credentials = new NetworkCredential("account", "password");
string Frasi1 = "ftp://epiz_27426656#ftpupload.net/htdocs/" + "Obiettivo" + ".json";
string contents1 = await clientw.DownloadStringTaskAsync(Frasi1);
ObservableCollection<FraseClass> FrasiJsonOnline1 = JsonConvert.DeserializeObject<ObservableCollection<FraseClass>>(contents1);
Frasi.ItemsSource = FrasiJsonOnline1;
ViewFrasi.IsVisible = true;
model.myBackGroundColor = Color.Transparent;
model.Vis = true;
list.Clear();
foreach (ClassCategory cat in selected)
{
list.Add(cat.Titolo);
}
}

I make a code sample with the part for the pre-selection or your reference.
Xaml:
<ContentPage.Content>
<CollectionView
x:Name="CategoryView"
Margin="10,0,10,0"
HeightRequest="700"
ItemsSource="{Binding classCategories}"
SelectedItems="{Binding SelectedCategories}"
SelectionChanged="CategoryView_SelectionChanged"
SelectionMode="Multiple">
<CollectionView.Footer>
<Button BackgroundColor="Transparent" HeightRequest="120" />
</CollectionView.Footer>
<CollectionView.ItemsLayout>
<GridItemsLayout
HorizontalItemSpacing="4"
Orientation="Vertical"
Span="2"
VerticalItemSpacing="1" />
</CollectionView.ItemsLayout>
<CollectionView.ItemTemplate>
<DataTemplate>
<Grid>
<!-- BackgroundColor="{Binding myBackGroundColor}" -->
<Grid.RowDefinitions>
<RowDefinition Height="36" />
<RowDefinition Height="33" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="30" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Image
Grid.Row="0"
Grid.RowSpan="2"
Grid.Column="0"
Grid.ColumnSpan="2"
Source="{Binding Image}" />
<Label
Grid.Row="1"
Grid.Column="0"
Grid.ColumnSpan="2"
Margin="13,0,0,0"
FontAttributes="Bold"
FontSize="19"
Text="{Binding Titolo}"
TextColor="White" />
<Image
Grid.Row="0"
Grid.Column="0"
Margin="13,5,0,0"
IsVisible="{Binding Vis}"
Source="pink.jpg" />
</Grid>
</DataTemplate>
</CollectionView.ItemTemplate>
</CollectionView>
Code behind:
public partial class MainPage : ContentPage, INotifyPropertyChanged
{
public ObservableCollection<ClassCategory> classCategories { get; set; }
public ObservableCollection<object> SelectedCategories { get; set; }
public MainPage()
{
InitializeComponent();
classCategories = new ObservableCollection<ClassCategory>()
{
new ClassCategory{ Image="pink.jpg", myBackGroundColor="Red", Titolo="A", Vis=true},
new ClassCategory{ Image="pink.jpg", myBackGroundColor="Green", Titolo="B", Vis=false},
new ClassCategory{ Image="pink.jpg", myBackGroundColor="Red", Titolo="A", Vis=true},
new ClassCategory{ Image="pink.jpg", myBackGroundColor="Green", Titolo="B", Vis=false},
new ClassCategory{ Image="pink.jpg", myBackGroundColor="Red", Titolo="A", Vis=true},
new ClassCategory{ Image="pink.jpg", myBackGroundColor="Green", Titolo="B", Vis=false},
new ClassCategory{ Image="pink.jpg", myBackGroundColor="Red", Titolo="A", Vis=true},
new ClassCategory{ Image="pink.jpg", myBackGroundColor="Green", Titolo="B", Vis=false},
new ClassCategory{ Image="pink.jpg", myBackGroundColor="Red", Titolo="A", Vis=true},
new ClassCategory{ Image="pink.jpg", myBackGroundColor="Green", Titolo="B", Vis=false},
};
SelectedCategories = new ObservableCollection<object>()
{
classCategories[0], classCategories[3]
};
this.BindingContext = this;
}
int i;
private void CategoryView_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
i++;
if (i <= 2)//this event would be trigglled twice before you load the page
{
return;
}
else
{
// var selected = e.CurrentSelection;
// ClassCategory model = e.CurrentSelection.FirstOrDefault() as ClassCategory;
// WebClient clientw = new WebClient();
// clientw.Credentials = new NetworkCredential("account", "password");
// string Frasi1 = "ftp://epiz_27426656#ftpupload.net/htdocs/" + "Obiettivo" + ".json";
// string contents1 = await clientw.DownloadStringTaskAsync(Frasi1);
// ObservableCollection<FraseClass> FrasiJsonOnline1 = JsonConvert.DeserializeObject<ObservableCollection<FraseClass>>(contents1);
// Frasi.ItemsSource = FrasiJsonOnline1;
// ViewFrasi.IsVisible = true;
// model.myBackGroundColor = Color.Transparent;
// model.Vis = true;
// list.Clear();
// foreach (ClassCategory cat in selected)
// {
// list.Add(cat.Titolo);
// }
}
}
}
public class ClassCategory
{
public string myBackGroundColor { get; set; }
public string Image { get; set; }
public string Titolo { get; set; }
public bool Vis { get; set; }
}

Delete sqlite data in listview on uwp

I have a listview whose data is extracted from sqlite database, as shown below:
I want to check the user click the delete button, then the data on the list is deleted and the data in the sqlite database also deleted.
XAML:
<ListView x:Name="ListTryout" Grid.Row="1" Margin="0,5,0,10" ItemsSource="{Binding Source={StaticResource itemsViewSource}}" DataContext="{Binding SelectedItem, ElementName=itemListView}" IsItemClickEnabled="True" SelectionChanged="ListTryout_SelectionChanged" Background="{x:Null}" SelectionMode="Single">
<ListView.ItemTemplate>
<DataTemplate>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="auto"/>
</Grid.ColumnDefinitions>
<StackPanel Grid.Column="0" Orientation="Vertical">
<TextBlock Margin="10,10,0,0" FontSize="20" Text="{Binding Judul}" Style="{StaticResource CaptionTextBlockStyle}" VerticalAlignment="Top" HorizontalAlignment="Left"/>
<TextBlock Margin="10,10,0,0" FontSize="17" Text="{Binding JumlahSoal}" VerticalAlignment="Top" HorizontalAlignment="Left" FontWeight="SemiLight"/>
<TextBlock Margin="10,10,0,0" FontSize="17" Text="{Binding Durasi}" VerticalAlignment="Top" HorizontalAlignment="Left" FontWeight="SemiLight" Visibility="Collapsed"/>
<Line X1="0" X2="1" Stretch="Fill" Margin="10,10,10,0" Stroke="#FF4B4B4B"/>
</StackPanel>
<AppBarButton x:Name="deleteItemBtn" Grid.Column="1" Margin="0,0,50,0" Icon="Delete" HorizontalAlignment="Right" Click="deleteItemBtn_Click"/>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
Code:
private void ReadTryoutList_Loaded(object sender, RoutedEventArgs e)
{
ReadAllDBName dbName = new ReadAllDBName();
DB_TryoutList = dbName.GetAllDBName();
ListTryout.ItemsSource = DB_TryoutList.OrderByDescending(i => i.ID).ToList();//Binding DB data to LISTBOX and Latest contact ID can Display first.
if(DB_TryoutList.Count == 0)
{
statuskosongStack.Visibility = Visibility.Visible;
ListTryout.Visibility = Visibility.Collapsed;
}
else
{
statuskosongStack.Visibility = Visibility.Collapsed;
ListTryout.Visibility = Visibility.Visible;
}
}
private void deleteItemBtn_Click(object sender, RoutedEventArgs e)
{
Db_Helper.DeleteQuiz(currentquiz.ID);
}
DatabaseHelper class:
public void CreateDatabase(string DB_PATH)
{
if (!CheckFileExists(DB_PATH).Result)
{
using (SQLite.Net.SQLiteConnection conn = new SQLite.Net.SQLiteConnection(new SQLite.Net.Platform.WinRT.SQLitePlatformWinRT(), DB_PATH))
{
conn.CreateTable<DBName>();
}
}
}
private async Task<bool> CheckFileExists(string fileName)
{
try
{
var store = await Windows.Storage.ApplicationData.Current.LocalFolder.GetFileAsync(fileName);
return true;
}
catch
{
return false;
}
}
// Insert the new history in the DBName table.
public void Insert(DBName dBName)
{
using (SQLite.Net.SQLiteConnection conn = new SQLite.Net.SQLiteConnection(new SQLite.Net.Platform.WinRT.SQLitePlatformWinRT(), App.DB_PATH))
{
conn.RunInTransaction(() =>
{
conn.Insert(dBName);
});
}
}
public DBName ReadName(int quizid)
{
using (SQLite.Net.SQLiteConnection conn = new SQLite.Net.SQLiteConnection(new SQLite.Net.Platform.WinRT.SQLitePlatformWinRT(), App.DB_PATH))
{
var existingName = conn.Query<DBName>("select * from DBName where ID =" + quizid).FirstOrDefault();
return existingName;
}
}
public ObservableCollection<DBName> ReadAllDBName()
{
try
{
using (SQLite.Net.SQLiteConnection conn = new SQLite.Net.SQLiteConnection(new SQLite.Net.Platform.WinRT.SQLitePlatformWinRT(), App.DB_PATH))
{
List<DBName> myCollection = conn.Table<DBName>().ToList<DBName>();
ObservableCollection<DBName> DBNameList = new ObservableCollection<DBName>(myCollection);
return DBNameList;
}
}
catch
{
return null;
}
}
public void DeleteQuiz(string ID)
{
using (SQLite.Net.SQLiteConnection conn = new SQLite.Net.SQLiteConnection(new SQLite.Net.Platform.WinRT.SQLitePlatformWinRT(), App.DB_PATH))
{
var existingquiz = conn.Query<DBName>("delete from DBName where ID ='" + ID + "'").FirstOrDefault();
if (existingquiz != null)
{
conn.RunInTransaction(() =>
{
conn.Delete(existingquiz);
});
}
}
}
I tried it, but the data can not be deleted on listview and also on the sqlite database.
How to handle it?

Set or bind the ItemsSource of the ListView to an ObservableCollection<T> and remove the item from this one, e.g.:
private ObservableCollecton<DBName> _source;
private void ReadTryoutList_Loaded(object sender, RoutedEventArgs e)
{
ReadAllDBName dbName = new ReadAllDBName();
DB_TryoutList = dbName.GetAllDBName();
_source = new ObservableCollecton<DBName>(DB_TryoutList.OrderByDescending(i => i.ID).ToList());
ListTryout.ItemsSource = _source;
if (DB_TryoutList.Count == 0)
{
statuskosongStack.Visibility = Visibility.Visible;
ListTryout.Visibility = Visibility.Collapsed;
}
else
{
statuskosongStack.Visibility = Visibility.Collapsed;
ListTryout.Visibility = Visibility.Visible;
}
}
private void deleteItemBtn_Click(object sender, RoutedEventArgs e)
{
var btn = sender as AppBarButton;
var item = btn.DataContext as DBName;
if (item != null)
{
_source.Remove(item);
Db_Helper.DeleteQuiz(currentquiz.ID);
}
}
I assume that GetAllDBName() are returning an IEnumerable<DBName> and that you are displaying DBNames in the ListView.

Why is my textbox loaded text disappearing

I have a textbox ACLBox that I want to display a string upon initialization of the user interface. Upon initializing, the string flashes for a second then disappears. Why?
Here's the xaml code for the textbox:
<Window x:Class="Funnel.ACL"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:Funnel"
mc:Ignorable="d"
Title="ACL Configuration" Height="300" Width="560" WindowStartupLocation="CenterScreen"
Closing="exitACL"
Background="LightGray" Name="ACLConfiguration">
<Grid>
<DockPanel>
<Grid x:Name="FunnelGrid" DockPanel.Dock="Top" ShowGridLines="False">
<!--Defining Grid-->
<Grid.ColumnDefinitions>
<ColumnDefinition Width="130"/>
<ColumnDefinition Width="40"/>
<ColumnDefinition Width="40"/>
<ColumnDefinition Width="40"/>
<ColumnDefinition Width="40"/>
<ColumnDefinition Width="30"/>
<ColumnDefinition Width="70"/>
<ColumnDefinition Width="75"/>
<ColumnDefinition Width="75"/>
<ColumnDefinition Width="75"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Label x:Name="Config"
Content="ACL CONFIGURATION"
Grid.Row="0"
Grid.Column="0"
Grid.ColumnSpan="9"
HorizontalAlignment="Center"
Foreground="Blue"
FontWeight="Heavy"
FontSize="16">
</Label>
<CheckBox x:Name="aclCheckbox"
FlowDirection="RightToLeft"
Content="ACL ON"
Foreground="Blue"
FontWeight="Heavy"
FontSize="16"
Grid.Row="1"
Grid.Column="0"
Grid.RowSpan="1"
Grid.ColumnSpan="5"
HorizontalAlignment="Center"
Checked="ACL_Check"
Unchecked="ACL_Unchecked"
/>
<Label x:Name="AddIPAddress" Content="Add IP Address" Grid.Row="2" Grid.Column="0" Width="90" Height="30"></Label>
<TextBox x:Name="AddIPTextBox1" Grid.Row="2" Grid.Column="1" Width="35" Height="20" TextChanged="AddIPTextBox1_TextChanged"></TextBox>
<TextBox x:Name="AddIPTextBox2" Grid.Row="2" Grid.Column="2" Width="35" Height="20" TextChanged="AddIPTextBox2_TextChanged"></TextBox>
<TextBox x:Name="AddIPTextBox3" Grid.Row="2" Grid.Column="3" Width="35" Height="20" TextChanged="AddIPTextBox3_TextChanged"></TextBox>
<TextBox x:Name="AddIPTextBox4" Grid.Row="2" Grid.Column="4" Width="35" Height="20" TextChanged="AddIPTextBox4_TextChanged"></TextBox>
<TextBox x:Name="AddErrorBox" Grid.Row="3" Grid.Column="0" Grid.ColumnSpan="2" HorizontalAlignment="Right" BorderThickness="0" Background="LightGray" FontSize="10" Text="{Binding AddErrorText}"/>
<Button x:Name="AddButton" Grid.Row="3" Grid.Column="1" Grid.ColumnSpan="4" HorizontalAlignment="Center" Height="25" Width="50" Click="addClick" FontSize="12" FontWeight="ExtraBold" Background="LightSteelBlue" VerticalAlignment="Top">ADD</Button>
<Label x:Name="DelIPAddress" Content="Remove IP Address" Grid.Row="4" Grid.Column="0" Width="120" Height="30"></Label>
<TextBox x:Name="DeleteIPTextBox1" Grid.Row="4" Grid.Column="1" Width="35" Height="20" TextChanged="DeleteIPTextBox1_TextChanged"></TextBox>
<TextBox x:Name="DeleteIPTextBox2" Grid.Row="4" Grid.Column="2" Width="35" Height="20" TextChanged="DeleteIPTextBox2_TextChanged"></TextBox>
<TextBox x:Name="DeleteIPTextBox3" Grid.Row="4" Grid.Column="3" Width="35" Height="20" TextChanged="DeleteIPTextBox3_TextChanged"></TextBox>
<TextBox x:Name="DeleteIPTextBox4" Grid.Row="4" Grid.Column="4" Width="35" Height="20" TextChanged="DeleteIPTextBox4_TextChanged"></TextBox>
<TextBox x:Name="DelErrorBox" Grid.Row="5" Grid.Column="0" Grid.ColumnSpan="2" HorizontalAlignment="Right" BorderThickness="0" Background="LightGray" FontSize="10" Text="{Binding DelErrorText}"/>
<Button x:Name="DeleteButton" Grid.Row="5" Grid.Column="1" Grid.ColumnSpan="4" HorizontalAlignment="Center" Height="25" Width="50" Click="deleteClick" FontSize="12" FontWeight="ExtraBold" Background="LightSteelBlue" VerticalAlignment="Top">DELETE</Button>
<Button x:Name="DeleteAllButton" Grid.Row="6" Grid.Column="1" Grid.ColumnSpan="4" HorizontalAlignment="Center" Height="25" Width="80" Click="deleteAllClick" FontSize="12" FontWeight="ExtraBold" Background="LightSteelBlue" VerticalAlignment="Top">REMOVE ALL</Button>
<Label x:Name="ACLBoxLabel" Content="Access Control List" Foreground="Blue" Grid.Row="1" Grid.Column="6" Grid.ColumnSpan="3" HorizontalAlignment="Center"></Label>
<TextBox x:Name="ACLBox"
ScrollViewer.HorizontalScrollBarVisibility="Auto"
ScrollViewer.VerticalScrollBarVisibility="Auto"
ScrollViewer.CanContentScroll="True"
Grid.Row="2"
Grid.Column="6"
Grid.RowSpan="4"
Grid.ColumnSpan="4"
HorizontalAlignment="Left"
VerticalAlignment="Center"
Width="220"
Height="150"
FontSize="14"
IsReadOnly="True"
Text="{Binding ACLBoxText}"
TextWrapping="Wrap"
TextAlignment="Center" />
</Grid>
</DockPanel>
</Grid>
Here's the C# code for the string:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
namespace Funnel
{
/// <summary>
/// Interaction logic for ACL.xaml
/// </summary>
public partial class ACL : Window
{
AclManager _manage = new AclManager();
FileController _controller = new FileController();
string addStr1;
string addStr2;
string addStr3;
string addStr4;
bool addError;
string delStr1;
string delStr2;
string delStr3;
string delStr4;
bool delError;
public string aclText;
public event PropertyChangedEventHandler PropertyChanged;
public ACL()
{
InitializeComponent();
if(FunnelGlobals.accessControlList)
{
aclCheckbox.IsChecked = true;
}
aclText = _manage.getAclList();
}
private void exitACL(object sender,System.ComponentModel.CancelEventArgs e)
{
_controller.writeAclFile();
}
private void ACL_Check(object sender, RoutedEventArgs e)
{
FunnelGlobals.accessControlList = true;
aclText = _manage.getAclList();
}
private void ACL_Unchecked(object sender, RoutedEventArgs e)
{
FunnelGlobals.accessControlList = false;
aclText = _manage.getAclList();
}
private void AddIPTextBox1_TextChanged(object sender, TextChangedEventArgs e)
{
AddErrorBox.Text = "";
AddIPTextBox1.Text = AddIPTextBox1.Text;
addStr1 = AddIPTextBox1.Text;
if(!_manage.isDigit(addStr1))
{
Color foreColor = (Color)new ColorConverter().ConvertFrom("red");
Brush errBrush = new SolidColorBrush(foreColor);
AddErrorBox.Foreground = errBrush;
AddErrorBox.Text = "Character NOT Valid";
addError = true;
}
else
{
addError = false;
}
ACLBox.Text = _manage.getAclList();
}
private void AddIPTextBox2_TextChanged(object sender, TextChangedEventArgs e)
{
AddErrorBox.Text = "";
AddIPTextBox2.Text = AddIPTextBox2.Text;
addStr2 = AddIPTextBox2.Text;
if (!_manage.isDigit(addStr2))
{
Color foreColor = (Color)new ColorConverter().ConvertFrom("red");
Brush errBrush = new SolidColorBrush(foreColor);
AddErrorBox.Foreground = errBrush;
AddErrorBox.Text = "Character NOT Valid";
}
aclText = _manage.getAclList();
}
private void AddIPTextBox3_TextChanged(object sender, TextChangedEventArgs e)
{
AddErrorBox.Text = "";
AddIPTextBox3.Text = AddIPTextBox3.Text;
addStr3 = AddIPTextBox3.Text;
if (!_manage.isDigit(addStr3))
{
Color foreColor = (Color)new ColorConverter().ConvertFrom("red");
Brush errBrush = new SolidColorBrush(foreColor);
AddErrorBox.Foreground = errBrush;
AddErrorBox.Text = "Character NOT Valid";
}
aclText = _manage.getAclList();
}
private void AddIPTextBox4_TextChanged(object sender, TextChangedEventArgs e)
{
AddErrorBox.Text = "";
AddIPTextBox4.Text = AddIPTextBox4.Text;
addStr4 = AddIPTextBox4.Text;
if (!_manage.isDigit(addStr4))
{
Color foreColor = (Color)new ColorConverter().ConvertFrom("red");
Brush errBrush = new SolidColorBrush(foreColor);
AddErrorBox.Foreground = errBrush;
AddErrorBox.Text = "Character NOT Valid";
}
aclText = _manage.getAclList();
}
private void addClick(object sender, RoutedEventArgs e)
{
String addStr = addStr1 + "." + addStr2 + "." + addStr3 + "." + addStr4;
if(_manage.isLegit(addStr))
{
FunnelGlobals.aclIPs.Add(addStr);
}
if(addError)
{
Color foreColor = (Color)new ColorConverter().ConvertFrom("red");
Brush errBrush = new SolidColorBrush(foreColor);
AddErrorBox.Foreground = errBrush;
AddErrorBox.Text = "Fix Invalid Characters before Adding";
}
else
{
aclText = _manage.getAclList();
}
}
private void DeleteIPTextBox1_TextChanged(object sender, TextChangedEventArgs e)
{
DelErrorBox.Text = "";
DeleteIPTextBox1.Text = DeleteIPTextBox1.Text;
delStr1 = DeleteIPTextBox1.Text;
if (!_manage.isDigit(delStr1))
{
Color foreColor = (Color)new ColorConverter().ConvertFrom("red");
Brush errBrush = new SolidColorBrush(foreColor);
DelErrorBox.Foreground = errBrush;
DelErrorBox.Text = "Character NOT Valid";
delError = true;
}
else
{
delError = false;
}
}
private void DeleteIPTextBox2_TextChanged(object sender, TextChangedEventArgs e)
{
DelErrorBox.Text = "";
DeleteIPTextBox2.Text = DeleteIPTextBox2.Text;
delStr2 = DeleteIPTextBox2.Text;
if (!_manage.isDigit(delStr2))
{
Color foreColor = (Color)new ColorConverter().ConvertFrom("red");
Brush errBrush = new SolidColorBrush(foreColor);
DelErrorBox.Foreground = errBrush;
DelErrorBox.Text = "Character NOT Valid";
delError = true;
}
else
{
delError = false;
}
}
private void DeleteIPTextBox3_TextChanged(object sender, TextChangedEventArgs e)
{
DelErrorBox.Text = "";
DeleteIPTextBox3.Text = DeleteIPTextBox3.Text;
delStr3 = DeleteIPTextBox3.Text;
if (!_manage.isDigit(delStr3))
{
Color foreColor = (Color)new ColorConverter().ConvertFrom("red");
Brush errBrush = new SolidColorBrush(foreColor);
DelErrorBox.Foreground = errBrush;
DelErrorBox.Text = "Character NOT Valid";
delError = true;
}
else
{
delError = false;
}
}
private void DeleteIPTextBox4_TextChanged(object sender, TextChangedEventArgs e)
{
DelErrorBox.Text = "";
DeleteIPTextBox4.Text = DeleteIPTextBox4.Text;
delStr4 = DeleteIPTextBox4.Text;
if (!_manage.isDigit(delStr4))
{
Color foreColor = (Color)new ColorConverter().ConvertFrom("red");
Brush errBrush = new SolidColorBrush(foreColor);
DelErrorBox.Foreground = errBrush;
DelErrorBox.Text = "Character NOT Valid";
delError = true;
}
else
{
delError = false;
}
}
private void deleteClick(object sender, RoutedEventArgs e)
{
String delStr = delStr1 + "." + delStr2 + "." + delStr3 + "." + delStr4;
FunnelGlobals.aclIPs.Remove(delStr);
if (delError)
{
Color foreColor = (Color)new ColorConverter().ConvertFrom("red");
Brush errBrush = new SolidColorBrush(foreColor);
DelErrorBox.Foreground = errBrush;
DelErrorBox.Text = "Fix Invalid Characters before Removing";
}
else
{
aclText = _manage.getAclList();
}
}
private void deleteAllClick(object sender, RoutedEventArgs e)
{
FunnelGlobals.aclIPs.Clear();
aclText = _manage.getAclList();
}
private void ACLBox_Loaded(object sender, RoutedEventArgs e)
{
ACLBox.Text = _manage.getAclList();
}
public string ACLBoxText
{
get { return aclText; }
set { aclText = value; OnNotifyPropertyChanged("ACLBoxText"); }
}
private void OnNotifyPropertyChanged(string v)
{
var handler = PropertyChanged;
if (handler != null)
handler(this, new PropertyChangedEventArgs(v));
throw new NotImplementedException();
}
}
}

Upon initializing, the string flashes for a second then disappears. Why?
Probably because you are "overwriting" the value of the ACLBoxText source property, which is initially displayed in the TextBlock, when you set the Text property of the TextBlock in your Loaded event handler.
If the TextBlock is empty once the UI has been loaded you should make sure that the _manage.getAclList() method returns the string that you expect it to return. You could temporarily try to assign the Text property to a "static" value:
private void ACLBox_Loaded(object sender, RoutedEventArgs e)
{
ACLBox.Text = "TEXT";
}
But I agree that it doesn't make much sense to first bind the Text property of the TextBlock to a source property in the XAML markup and then handle the Loaded event of the same TextBlock and set its Text property to a new value in this event handler. But I guess you have your reasons...
Note that binding that you define in the XAML markup will get reset when you programmatically set the Text property in your Loaded handler though.
So you should either don't bind the Text property in the XAML markup, or don't handle the Loaded event and set the Text property programmatically. It's one or the other but not both.

I figured out the problem. This is my first C# project and first time ever using Xaml (wpf) so I misunderstood binding. I bound the text like I did in the primary gui. The text is never getting triggered within this gui so I could only see the text flash because of loaded but then the text binding reset the textbox to nothing. When I changed my text to not be bound then everything works as I wanted. Lesson learned. Binding is only needed when accessing a textbox from within .cs files. It is not needed within xaml.cs. Since my text would only ever be triggered by xaml.cs just setting text the usual way(ie textbox.text = "whatever") does what I need. Thank you everyone for your help. I understand binding much, much better now. Java does things differently. :)

As Ed Plunkett has already mentioned, you should use your ACLBoxText backing variable instead of resetting the control value.
Something like this will work:
private void ACLBox_Loaded(object sender, RoutedEventArgs e)
{
ACLBoxText = _manage.getAclList();
}
Unfortunately, the view doesn't know about changes to backing properties unless you tell it that something changed. You need to implement INotifyPropertyChanged:
private string _aclBoxText;
public string ACLBoxText {
get { return _aclBoxText; }
set {
_aclBoxText = value;
OnNotifyPropertyChanged("ACLBoxText");
}
}
protected void OnNotifyPropertyChanged(string name)
{
var handler = PropertyChanged;
if (handler != null)
handler(this, new PropertyChangedEventArgs(name));
}
public event PropertyChangedEventHandler PropertyChanged;

Infinity scroll bug with data template

After user get the end of longlistselector ItemRealized event fires items add successfully. But the button's tag is empty (for added items), for items that I got first time button's tag isn't null.
This is my xaml DataTemplate:
<DataTemplate x:Key="TitleSongDataTemplate" x:Name="Titledata">
<Border Background="{StaticResource PhoneForegroundBrush}" Margin="0,0,12,12">
<Grid x:Name="GridOfButtons" Background="{StaticResource PhoneForegroundBrush}" >
<Grid Margin="0, -6, -7, 0"
HorizontalAlignment="Right"
VerticalAlignment="Top" Height="81" Width="83">
<Button
Content=""
FontFamily="Segoe UI Symbol"
Style="{StaticResource RoundButton}"
x:Name="AddToMySongsButton"
Tag="{Binding Song}"
Background="{StaticResource PhoneBackgroundBrush}"
Click="AddToMySongsButton_Click"/>
</Grid>
<Grid
VerticalAlignment="Top"
HorizontalAlignment="Left"
Margin="-17,-6,0,0" Height="81" Width="95">
<Button FontFamily="Segoe UI Symbol"
Content=""
Style="{StaticResource RoundButton}" Margin="10,0,0,0"
x:Name="PlayButton"
Background="{StaticResource PhoneBackgroundBrush}"
Tag="{Binding Song}"
Click="PlayButton_Click"/>
</Grid>
<Grid
HorizontalAlignment="Center"
VerticalAlignment="Top"
Margin="69,-7,60,0" Height="82" Width="84">
<Button Style="{StaticResource RoundButton}"
Content=""
FontFamily="Segoe UI Symbol"
x:Name="DownloadButton"
Margin="-5,0,0,0"
Background="{StaticResource PhoneBackgroundBrush}"
Tag="{Binding Song}"
Click="DownloadButton_Click"/>
</Grid>
<StackPanel VerticalAlignment="Bottom">
<TextBlock Text="{Binding Title}" Foreground="{StaticResource PhoneBackgroundBrush}" Margin="6 , 4, 6, 4"/>
<TextBlock Text="{Binding Artist}" Foreground="Gray" Opacity="0.75" Margin="6, 0, 0, 6"/>
</StackPanel>
</Grid>
</Border>
</DataTemplate>
My pivot:
<phone:Pivot x:Name="MainTitle">
<phone:PivotItem Header="Rock">
<Grid>
<phone:LongListSelector x:Name="RockLongList"
GridCellSize="220,150"
LayoutMode="Grid"
ItemTemplate="{StaticResource TitleSongDataTemplate}"
ItemRealized="RockLongList_ItemRealized"/>
<TextBlock x:Name="RockText"
Text="Загрузка..."
FontSize="60"
Opacity="0.5"
Style="{StaticResource LongListSelectorGroupHeaderLetterTileStyle}"
Margin="0,10,10,10"
TextWrapping="Wrap"
HorizontalAlignment="Right"
Width="436"/>
</Grid>
</phone:PivotItem>
Here my infinity scrooling realization:
1.I fired ItemRealized
private void RockLongList_ItemRealized(object sender, ItemRealizationEventArgs e)
{
var nownum = offset + 50;
if (nownum >= usercount)
{
MainTitle.Title = "All songs've downloaded";
}
else
{
SpecialSongs.SongJSON song = e.Container.Content as SpecialSongs.SongJSON;
if (song != null)
{
int myoffset = 2;
// Only if there is no data that is currently getting loaded would be initiate the loading again
if (!isCurrentlyLoading && defaultBindList.Count - defaultBindList.IndexOf(song) <= myoffset)
{
LoadDataFromSource();
}
}
}
}
And finally:
private void LoadDataFromSource()
{
this.Dispatcher.BeginInvoke(() =>
{
MainTitle.Title = "Downloading test...";
});
//progressBar.IsVisible = true;
isCurrentlyLoading = true;
string UsersUri = string.Format("https://api.vk.com/method/audio.get?&count=50&access_token={0}&user_id={1}&version=4.92&offset={2}", AccessToken, uID, offset);
//var query = string.Format(datasourceUrl, currentPage);
WebClient client = new WebClient();
client.DownloadStringCompleted += client_DownloadStringCompleted;
client.DownloadStringAsync(new Uri(UsersUri));
}
private void client_DownloadStringCompleted(object sender, DownloadStringCompletedEventArgs e)
{
//Here handle exception
using (var reader = new MemoryStream(Encoding.Unicode.GetBytes(e.Result)))
{
SpecialSongs songs = JsonConvert.DeserializeObject<SpecialSongs>(e.Result);
this.Dispatcher.BeginInvoke(() =>
{
foreach (var tracks in songs.songs)
{
rockBindList.Add(tracks);
MainTitle.Title = "Downloaded test...";
}
RockLongList.ItemsSource = rockBindList;
isCurrentlyLoading = false;
//progressBar.IsVisible = false;
});
}
offset += 50;
}
This code shows why i need button's tag property:
private void DownloadButton_Click(object sender, RoutedEventArgs e)
{
try
{
SpecialSongs.SongJSON songdgd = (SpecialSongs.SongJSON)(sender as Button).Tag;
this.Download.Message = songdgd.Artist + "\n" + songdgd.Title;
string StringToSave = "shared/transfers/" + songdgd.Artist + songdgd.Title;
var linktosave = StringToSave.Replace(" ", "");
transferRequest = new BackgroundTransferRequest(new Uri(songdgd.URI, UriKind.RelativeOrAbsolute)) { Method = "GET" };
var uri = new Uri(linktosave, UriKind.Relative);
songdgd.URI = linktosave.Replace("shared/transfers/", "");
var json = JsonConvert.SerializeObject(songdgd);
var name = linktosave.Replace("shared/transfers/", "");
transferRequest.Tag = "json" + json + "json" + "uri" + name + "uri";
transferRequest.TransferPreferences = TransferPreferences.AllowCellularAndBattery;
transferRequest.DownloadLocation = uri;
try
{
BackgroundTransferService.Add(transferRequest);
}
catch
{
MessageBox.Show("Эта песня уже загружается.");
}
}
catch { MessageBox.Show("Error while downloading"); }
}
Thanks.